The state or condition of being parallel; agreement in direction, tendency, or character.
A guide to parallelism
• The state of being in agreement or similarity; resemblance, correspondence, analogy.
• A parallel position; the relation of parallels.
• The juxtaposition of two or more identical or equivalent syntactic constructions, especially those expressing the same sentiment with slight modifications, introduced for rhetorical effect.
• The doctrine that matter and mind do not causally interact but that physiological events in the brain or body nonetheless occur simultaneously with matching events in the mind.
• In antitrust law, the practice of competitors of raising prices by roughly the same amount at roughly the same time, without engaging in a formal agreement to do so.
• Similarity of features between two species resulting from their having taken similar evolutionary paths following their initial divergence from a common ancestor.
• The use of parallel methods in hardware or software, so that several tasks can be performed at the same time.
Why parallelism is relevant in U.S. law
parallelism appears in U.S. legal practice across multiple practice areas. Knowing what it means — and when it applies — can determine the outcome of motions, filings, and negotiations. For non-lawyers, the value of looking up a precise definition is that legal terms often carry meanings that differ from everyday usage; relying on the common meaning can lead to costly missteps.
When and how parallelism applies
In practice, parallelism is invoked when parties, judges, or attorneys need to identify the legal status of an issue, the rights of those involved, or the procedural step required next. The definition shown above is sourced from Wiktionary , which is widely cited in U.S. legal practice. Because U.S. law is jurisdictionally layered — federal, state, and sometimes local — the precise application of the term can vary by court, so check the controlling authority for your specific case.